Reactive oxygen species activated NLRP3 inflammasomes prime environment-induced murine dry eye
Reactive oxygen species activated NLRP3 inflammasomes prime environment-induced murine dry eye
复制标题
活性氧激活的 NLRP3 炎症小体 Prime 环境诱发的小鼠干眼症
DOI：
10.1016/j.exer.2014.05.001
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发表时间：
2014-08-01
影响因子：
3.4
通讯作者：
Chen, Wei
中科院分区：
文献类型：
--
作者：
Zheng, Qinxiang;Ren, Yueping;Chen, Wei
泪膜高渗性沿着氧化应激是可诱导慢性眼表炎症和疼痛的因素。然而，关于氧化剂暴露产生的活性氧（ROS）增加如何诱导炎症的信息有限。在其他组织中有新的证据表明，对各种环境应激的先天性免疫应答源于ROS诱导的胞质NLRP 3炎性小体活化。一旦发生这种情况，半胱天冬酶原-1转化为其催化活性形式，其又切割IL-1 β原，从而产生其生物活性形式。我们在环境诱导的小鼠干眼（DE）模型中确定了ROS产生在介导IL-1 β分泌增加中的作用，所述IL-1 β分泌增加是通过NLRP 3炎性体激活引起的半胱天冬酶-1激活来实现的。智能控制环境系统（ICES）在雌性4-6周龄C57 BL/6 J小鼠中诱导蒸发性DE。ROS产生的增加先于角膜和结膜NLRP 3炎性体组分和IL-1 β基因表达的增加，这是使用实时PCR鉴定的。共聚焦显微镜评价了NLPR 3、caspase-1和IL-1 β免疫染色的伴随增加。半胱天冬酶-1活性的增加被用作炎性小体活化的指标。ROS产生的增加发生在ICES暴露1周后，这先于三种NLRP 3炎性体组分（即NLRP 3、ASC和半胱天冬酶-1）的基因表达增加，导致生物活性IL-1 β释放增加。ICES暴露2周后，caspase-1活性增加。将含有0.3%N-乙酰基-L-半胱氨酸（NAC）的滴眼剂应用于在ICES中保持2周的小鼠的ROS产生。这种清除剂减少了角膜荧光素染色并减少了ROS的产生。NAC还下调NLRP 3、ASC、半胱天冬酶-1和IL-1 β mRNA水平的增加，沿着其免疫染色。它强烈减弱炎症小体介导的caspase-1催化活性增加。我们在干燥性DE疾病小鼠模型中显示，ROS产生的增加触发NLRP 3炎性小体复合和活化，导致生物活性IL-1 β分泌增加。这些结果提示我们，ROS-NLRP 3-IL-1 β信号通路可能在环境诱导的DE进展中发挥启动作用。最后，我们的研究结果为开发新的策略提供了基础，这些策略可能会改善需要治疗环境诱导性干眼病的患者的管理。(C)2014爱思唯尔有限公司版权所有。
Tear film hyperosmolarity along with exposure to oxidant stress are factors that can induce chronic ocular surface inflammation and pain. However, there is limited information on how increases in reactive oxygen species (ROS) generated by oxidant exposure can induce inflammation. There is emerging evidence in other tissues that innate immune responses to a variety of environmental stresses stem from ROS-induced cytosolic NLRP3 inflammasome activation. Once this occurs, pro-caspase-1 is converted into its catalytic active form, which in turn cleaves pro-IL-1 beta thereby generating its bioactive form. We determined the role of ROS generation in mediating increases in IL-1 beta secretion through caspase-1 activation caused by NLRP3 inflammasome activation in an environment-induced murine dry eye (DE) model. An intelligently controlled environmental system (ICES) induced evaporative DE in female 4-6 week old C57BL/6J mice. Increases in ROS production preceded rises in corneal and conjunctival gene expression of NLRP3 inflammasome components and IL-1 beta that were identified using real-time PCR. Confocal microscopy evaluated concomitant increases in NLPR3, caspase-1 and IL-1 beta immunostaining. Increases in caspase-1 activity were used as an indicator of inflammasome activation. Rises in ROS generation occurred after I week of ICES exposure, which preceded increases in gene expression of three NLRP3 inflammasome components (i.e. NLRP3, ASC and caspase-1) leading to rises in bioactive IL-1 beta release. Increases in caspase-1 activity occurred after 2 weeks of ICES exposure. Eyedrops containing 0.3% N-acetyl-L-cysteine (NAC) were applied to quench ROS generation by mice kept in the ICES for 2 weeks. This scavenger reduced corneal fluorescein staining and decreased ROS production. NAC also down-regulated both increases in NLRP3, ASC, caspase-1 and IL-1 beta mRNA levels, along with their immunostaining. It robustly attenuated rises in inflammasome mediated increases in caspase-1 catalytic activity. We show in a dessicating DE disease murine model that rises in ROS generation trigger NLRP3 inflammasome complexation and activation leading to increases in bioactive IL-1 beta secretion. These results prompt us to suggest that the ROS-NLRP3-IL-1 beta signaling pathway might play a priming role in environment-induced DE progression. Finally, our findings provide a basis for developing novel strategies that may improve the management of patients requiring treatment for environment-induced dry eye disease. (C) 2014 Elsevier Ltd. All rights reserved.